Initial implementation for 'search.findElementReferences'.

pkg/analysis_server/lib/src/search/element_references.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library search.element_references;
+
+import 'dart:async';
+
+import 'package:analysis_server/src/search/search_result.dart';
+import 'package:analysis_services/search/search_engine.dart';
+import 'package:analyzer/src/generated/element.dart';
+import 'package:analyzer/src/generated/source.dart';
+
+
+/**
+ * A computer for `search.findElementReferences` request results.
+ */
+class ElementReferencesComputer {
+  final SearchEngine searchEngine;
+
+  ElementReferencesComputer(this.searchEngine);
+
+  /**
+   * Computes [SearchResult]s for [element] references.
+   */
+  Future<List<SearchResult>> compute(Element element, bool withPotential) {
+    var futures = <Future<List<SearchResult>>>[];
+    // tweak element
+    if (element is FieldFormalParameterElement) {
+      element = (element as FieldFormalParameterElement).field;
+    }
+    if (element is PropertyAccessorElement) {
+      element = (element as PropertyAccessorElement).variable;
+    }
+    // prepare Element(s) to find references to
+    List<Element> refElements = <Element>[];
+    if (element != null) {
+      // TODO(scheglov) find all hierarchy members
+//      if (element is ClassMemberElement) {
+//        refElements = HierarchyUtils.getHierarchyMembers(searchEngine, element);
+//      } else {
+//        refElements = <Element>[element];
+//      }
+      refElements = <Element>[element];
+    }
+    // process each 'refElement'
+    for (Element refElement in refElements) {
+      // add variable declaration
+      if (_isVariableLikeElement(refElement)) {
+        int nameOffset = refElement.nameOffset;
+        int nameLength = refElement.name.length;
+        SearchMatch searchMatch =
+            new SearchMatch(
+                MatchKind.DECLARATION,
+                refElement,
+                new SourceRange(nameOffset, nameLength),
+                true,
+                false);
+        SearchResult searchResult = new SearchResult.fromMatch(searchMatch);
+        futures.add(new Future.value(<SearchResult>[searchResult]));
+      }
+      // do search
+      Future<List<SearchMatch>> matchesFuture =
+          searchEngine.searchReferences(refElement);
+      Future<List<SearchResult>> resultsFuture =
+          matchesFuture.then((List<SearchMatch> matches) {
+        return matches.map(toResult).toList();
+      });
+      futures.add(resultsFuture);
+    }
+    // report potential references
+    if (withPotential) {
+      var matchesFuture = searchEngine.searchMemberReferences(element.name);
+      var resultsFuture = matchesFuture.then((List<SearchMatch> matches) {
+        return matches.where(
+            (match) => !match.isResolved).map(toResult).toList();
+      });
+      futures.add(resultsFuture);
+    }
+    // merge results
+    var futuresFuture = Future.wait(futures);
+    return futuresFuture.then((List<List<SearchResult>> lists) {
+      // TODO(scheglov) extract?
+      return lists.expand((List<SearchResult> matches) => matches).toList();
+    });
+  }
+
+  static SearchResult toResult(SearchMatch match) {
+    return new SearchResult.fromMatch(match);
+  }
+
+  static bool _isVariableLikeElement(Element element) {
+    if (element is LocalVariableElement) {
+      return true;
+    }
+    if (element is ParameterElement) {
+      return true;
+    }
+    if (element is PropertyInducingElement) {
+      return !element.isSynthetic;
+    }
+    return false;
+  }
+}